The genus Viola is included in the family Violaceae and has about 500 species of annuals, biennials, evergreen, and semi-evergreen and deciduous perennials found in varied habitats in temperate regions worldwide.
Each flower has 5 petals: a spurred lower petal, 2 lateral petals and 2 upward-facing upper petals.
While many cultivars within the genus are informally referred to as garden pansies, violas are all derived from the complex hybridization of V. tricolour, V. lutea, V. cornuta, and other species.
Viola cornuta has played an important role in the development of garden violas and violettas as a result of cross breeding with the garden pansy V. wittrocklana. 
Viola cornuta is stem prostrate, with leaves narrow to broad ovate, base cordate to truncate, and margin shallow-crenate.
The female parent used in the crossing of ‘Sunvioho’ was ‘9V-39a’ (unpatented in the U.S.) which is our breeding line and grown at Omori-cho, Yokaichi-shi, Shiga-ken, Japan
The pollen parent used in the crossing of ‘Sunvioho’ was ‘Alpine Sun’ (a cultivar unpatented in the U.S.).